Apparatus for dressing side surfaces of grinding wheels

ABSTRACT

In apparatus for dressing side surfaces of a grinding wheel, there are provided a base swung in a plane parallel to the side surfaces of the grinding wheel, a pair of rotary dressing tools journalled by a pair of supporting members mounted on the base on both sides of the grinding wheel, and a drive mechanism for rotating the dressing tools. In addition, there are further provided adjusting means for moving the supporting members and the rotary dressing tools toward and away from the side surfaces of the grinding wheel without the necessity of operating the drive mechanism.

United States Patent Fu'ii 1451 July 25, 1972 54] APPARATUS FOR DRESSINGSIDE 2,148,120 2/1939 Hall ..125/11 ST 2,077,363 4/1937 l-lulbert......125 11 ST SURFACES 0F GRINDING WHEELS 3,552,375 1 1971 Carr ..125 11c1) [72] Inventor: Tsuneji Fujii, Kariya, Japan Primary Examiner-HaroldD. Whitehead [73] Ass1gnee. Toyoda Kokl Kabushlkl Kaisha, Kariya- An0meywendemth Lind & Ponack shi, Japan [22] Filed: March 1, 1971 [57]ABSTRACT [21] Appl. No.: 119,496 In apparatus for dressing side surfacesof a grinding wheel, there are provided a base swung in a plane parallelto the side surfaces of the grinding wheel, a pair of rotary dressingtools [30] Forelgn Apphcauon Prmr'ty Data journalled by a pair ofsupporting members mounted on the March 30, 1970 Japan ..45/30465 baseon both Sides of the grinding Wheel, and a drive mechanism for rotatingthe dressing tools. In addition, there [52] U.S. Cl ..l25/ ll CD, l25/lI ST are further Provided adjusting means for moving FP 51 2' 53/14 ingmembers and the rotary dressing tools toward and away 53 1 Field ofSearch 125 1 1 from the Side Surfaces of the grinding Wheel Without thenecessity of operating the drive mechanism. [56] References Cited 8Claims, 4 Drawing Figures UN [TED STATES PATENTS 3,581,730 6/1971 Boyd..125/ll CD 11 F' r E 1112 1 10 I- 111 v I? I? I? Ill A14 in T PatentedJuly 25, 1972 3,678,916

4 Sheets-Sheet 1 If 'ENTOR ,7 MMMQZMMZ ATTORNEKS Patented July 25, 19723,678,916

4 Sheets-Sheet 2 INVENTOR Wfi/ AUMIMAC Z ATTORNEYS Patented July 25,1972 4 Sheets-Sheet 3 I? VENT 9R MM ATTORNEY Patented July 25, 19723,678,916

43heets-Sheet 4 Q a 9 an 5 0Q 2 a Q 5 E an; gm N o o O O o o o o 5 2 Q Q0 0P0 M n 5 .5

APPARATUS FOR DRESSING SIDE SURFACES OF GRINDING WHEELS BACKGROUND OFTHE INVENTION This invention relates to an improved apparatus fordressing the side surfaces of a grinding wheel.

In prior apparatus for dressing opposite surfaces of a grinding wheel byusing a single rotary dressing tool, the grinding wheel is forced to bedisplaced by the side pressure applied thereto by the rotary dressingtool, which results in a lower parallelism between side surfaces of thegrinding wheel. In addition, twice dressing operations are required todress a single grinding wheel. Thus, the efficiency of the operation islower.

Furthermore, in a prior dressing apparatus utilizing a rotary dressingtool, the rotary dressing tool is moved in its straight path of travelin a direction perpendicular to the axis of the grinding wheel, wherebya rapid wear takes place on the forward end periphery of the rotarydressing tool.

Moreover, in such prior dressing apparatus, as the shaft carrying therotary dressing tool is connected to a rotating driving mechanism, it isdifiicult to finely adjust the cutting depth of the dressing toolwithout adjustment of such driving mechanism.

SUMMARY OF THE INVENTION It is therefore an object of the presentinvention to provide a new and improved dressing apparatus forsimultaneously dressing opposite surfaces of a grinding wheel wherebythe grinding wheel is not displaced by the side pressure applied theretoby the rotary dressing tool.

Another object of the present invention is to provide an improvedapparatus for simultaneously dressing opposite side surfaces of agrinding wheel by utilizing a pair of swinging rotary dressing tools.

A further object of the present invention is to provide a novelapparatus for simultaneously dressing opposite surfaces of a grindingwheel which can provide fine adjustment of the cutting depth of therotary dressing tools without the recessity of operating a rotatingdriving mechanism.

According to the present invention, these and further objects can beaccomplished by providing a dressing apparatus comprising a base, meansto swing the base in a plane parallel to the side surfaces of thegrinding wheel, a pair of supporting members mounted on the base on theopposite sides of the grinding wheel, a first shaft rotatably mounted ineach of the supporting members, a rotary dressing tool mounted on eachfirst shaft, a second shaft drivingly connected to a driving means, anda drive connection between the second shaft and each first shaft.

In addition, there are further provided means to move each supportingmember and hence the rotary dressing tool associated therewith towardand away from each side surface of the grinding wheel and means toprevent the drive connection from being released upon movement of eachsupporting member toward and away from each side surface of the grindingwheel.

BRIEF DESCRIPTION OF THE DRAWINGS The invention can be move fullyunderstood from the following detailed description taken in conjunctionwith the accompanying drawings, in which:

FIG. 1 shows a cross-sectional view of a dressing apparatus embodyingthe invention;

FIG. 2 shows an enlarged section taken along a line IIII in FIG. 1;

FIG. 3 shows a section taken along a line IIIIII in FIG. 2 and FIG. 4shows an enlarged sectional view taken along a line IVIV in FIG. 1.

A preferred embodiment shown in the accompanying drawings comprises abase 1 supported on the rear side of a guard plate 7 to be rotatable ina plane parallel to the side surfaces of a plurality of grinding wheels3. Thus, the sleeve in of base 1 is rotatably mounted on a shaft 2through bearings. One end of shaft 2 being journalled in a casing 8secured on a grinding wheel carriage, not shown, in a manner not to bemovable in the axial direction. A plurality of pairs of supportingmembers 4 are adjustably mounted on the base 1 by bolts 36, each pair ofsupporting members 4 being disposed on the opposite sides of one of thegrinding wheels 3 mounted on a common shaft, not shown.

An intermediate shaft 5 is supported at its opposite ends by bearings 40and 41 mounted in casings 9 and 42, respectively, secured to the base 1(FIGS. 1, 3). The shaft 5 extends through the base portions 43 ofrespective supporting members 4 and is journalled by bearings 44 and 45mounted therein, as shown in FIG. 3. A bevel gear 11 keyed to one end ofshaft 5 is driven by a bevel gear 6 keyed to the shaft 19 of a drivingmotor 20 secured to casing 42. As best shown in FIG. 3, in eachsupporting member 4 is rotatablyjournalled a rotary shaft 12 at rightangles with respect to the intermediate shaft 5. A rotary dressing tool10 is secured to one end of each shaft 12 and a bevel gear 15 is keyedto the inner end thereof to mesh a corresponding bevel gear 16 keyed tointermediate shaft 5. Thus, when motor 20 is started, shafts 12 arerotated through gears 6 and 11, intermediate shaft 5 and gears 16 and15.

A collar 46, loosely mounted on the intermediate shaft 5, is disposedbetween bearing 45 and bevel gear 16 within the base portion 43 of eachsupporting member 4 to locate the bevel gear 16 in meshing engagementwith the bevel gear 15 of rotary shaft 12. Accordingly, when eachsupporting member 4 is moved for adjustment of cutting depth of rotarydressing tool 10, as described later in detail, the associated bearings44 and 45, bevel gear 16 and collar 46 are moved therewith as a unit,whereby the bevel gear 15 of the rotary shaft 12 is held in meshingengagement with its associated bevel gear 16.

A gear box 13 is securely fixed to the righthand side of guard plate 7,as viewed in FIG. 1. Housed in gear box 13 is a worm wheel 21 which issecured to one end of sleeve 1a of the base 1 and freely mounted on thedriving shaft 2 extending through the gear box 13. As shown in FIG. 4, aworm shaft 17.

with an integral worm 22 meshing worm wheel 21 is mounted in the gearbox 13 to be slidable in a direction perpendicular to driving shaft 2.One end of worm shaft 17 is connected to a piston 18, slidably receivedin a cylinder 14, in a manner to be rotatable but not movable in theaxial direction with respect thereto. Fluid ports 14a and 14b arecommunicated with a source of fluid under pressure via a change overvalve, not shown. Furthermore, a cylinder 23 is formed on the righthandside of gear box 13, as viewed in FIG. 4, to slidably receive a piston24 with integral piston rods 25 and 26 extending outwardly and inwardly,respectively of the gear box. Piston rod 25 carries a pair of spacedapart dogs 27a and 27b cooperating with limit switches 31a and 3112whereas the inner end of piston rod 26 cooperates with a stop 28 securedto the end surface of worm wheel 21. Stop 28 is arranged to engagepiston rod 26 in its left end position, as shown in FIG. 4 during aperiod in which the dressing operation of the grinding wheels 3 is notperformed to prevent rotation of worm wheel 21 so as to maintainsupporting members 4 and hence base 1 at the solid line position shownin FIG. 2. The lefthand chamber 23a and the righthand chamber 23b ofcylinder 23 are communicated with a source of fluid under pressure via achange over valve, not shown. Further, a pair of circumferentiallyspaced apart dogs 29a and 29b are secured to the end surface of wormwheel 21 to actuate limit switches 30a and 30b, respectively.Consequently, when the pressurized fluid is admitted into the lefthandchamber 23a of cylinder 23, piston 23 is moved to the right as viewed inFIG. 2 to disengage piston rod 26 from stop 28, thus permitting wormwheel 21 to rotate freely. Then, the

pressurized fluid is admitted into the cylinder 14 through port 14a toslide worm shaft 17 toward right as viewed in FIG. 4 to rotate wormwheel 21 through worm 22 whereby the base 1 is tilted about drivingshaft 2. Thus, the entire widths of rotary dressing tools 10 aresimultaneously brought into engagement with the grinding wheel, wherebythe grinding wheel is not displaced by the side pressures appliedthereto by the rotary dressing tools 10.

As shown in FIGS. 1, 2 and 3, plates 34 are securely fixed on base 1 onthe opposite sides of each pair of supporting members 4. As best shownin FIG. 3, an adjusting bolt 35 extends through each plate 34 in amanner not to be movable in the axial direction, the inner threaded endof the bolt being threaded into the supporting member 4. An elongatedguide 32 is secured on the upper surface of base 1 in parallel with theaxes of grinding wheels. The guide 32 is received in a groove 33 formedin the upper surface of base 1 beneath supporting members 4 and plates34 as shown in FIG. 2. Thus, the adjustment of the feed or cutting depthof the dressing tools 10 into the side surfaces of the grinding wheel 3is made by loosening bolts 36, and the rotating adjusting bolts 35 formoving supporting members 4 along guide 32.

The operation of the moved dressing apparatus is as follows. To dressopposite side surfaces of grinding wheels 3, at first driving motor 20is started to drive intermediate shaft 5 through bevel gears 6 and 11.The rotation of intermediate shaft 5 is transmitted to rotary dressingtools 10 through bevel gears 16 and and shafts 12. It should beunderstood that concurrently with the operation of motor 20 the shaftfor driving grinding wheels is also rotated by a driving motor notshown. Then, the pressurized fluid is admitted into lefthand chamber 23aof cylinder 23 of gear box 13 to drive piston 24 and piston rods 25 and26 to the right. As a consequence, piston rod 26 is disengaged from stop28 to release worm wheel 21. Movement of piston rod 25 causes dog 27a toactuate limit switch 31a to indicate the forward movement of piston 24.Responsive to the operation of limit switch 31a, the pressurized fluidis supplied to cylinder 14 through its port 14a to advance piston 18together with worm shaft 17 whereby worm wheel 21 is rotated. As abovedescribed, since worm wheel 21 is secured to sleeve 1a of base 1, base 1is tilted downwardly about driving shaft 2. Consequently, supportingmembers 4 are also rotated about shaft 2 from the solid line position tothe dot and dash line position shown in FIG. 2 to simultaneously dressboth side surfaces of each grinding wheel by the dressing tools 10carried by the supporting members. When dog 29a actuates limit switch30a mounted on gear box 13, the change over valve, not shown, isoperated to admit the pressurized fluid into cylinder 14 through port14b thus moving worm shaft 17 in the opposite direction. Accordingly,worm wheel 21 is roted in the opposite direction to restore base 1,supporting members 4 and dressing tools to the original position shownby solid lines. At this position, dog 29b operates the other limitswitch 30b to switch the change over valve to admit the pressurizedfluid into cylinder 14 through port 1412. In tlu's manner, rotarydressing tools 10 are continuously oscillated about shaft '2 to performthe dressing operation on both side surfaces of each grinding wheel 3.To adjust the cutting depth of respective dressing tools 10, whilesupporting members 4 are maintained at the solid line position,

bolts 36 are loosened and then adjusting'bolts are rotated to movesupporting members 4 along guide 32 together with shafts 12 and gears15, 16, bearings 44, 45 and collars 46 contained in the cylinders 4.Such adjustment is made several times until the width of each grindingwheel has been dressed to a predetermined width. Upon completion of thedressing operation supporting members 4 and dressing tools 10 arebrought back to the solid lineposition shown in FIG. 2, and the supplyof the pressurized fluid to cylinder 14is interrupted while at the sametime driving motor 20 is deenergized. The pressurized fluid is admittedinto the righthand chamber 23b of cylinder 23 to move piston 23 to theleft to engage piston rod 26 against stop 28 whereby the rotation ofsupporting members 4 is prevented. Since both side surfaces of eachgrinding wheel 3 are dressed simultaneously, side surfaces thereof arenever be displaced by the side pressures applied by rotary dressingtools thus assuring high accuracy of dressing. Furthermore, since theentire widths of rotary dressing tools are simultaneously brought intoengagement with each grinding wheel 3, weardoes not take place on theforward end periphery of each dressing tool 10. From the foregoingdescription it will be clear that the invention provides a novelapparatus for simultaneously dressing both side surfaces of a grindingwheel wherein supporting members for the both side surfaces are securedto a base supported in a guard plate to oscillate in a plane parallel tothe side surfaces of the grinding wheel, rotary dressing tools arerotatably joumalled in the supporting members and the supporting membersare moved along a guide by turning adjusting bolts threaded in thecylinders so as to adjust the cutting depth of the dressing tools. Withthis construction, it is possible not only to simultaneously dress bothside surfaces of the grinding wheel at a high efficiency but to preventthe displacement of the side surfaces caused by the side pressureapplied thereto by the dressing tools thus dressing these surfaces withextremely high accuracies. Since the adjustment of the cutting depth ofthe dressing tools is made without operating the driving mechanism ofthe rotary dressing tools such adjustment can be made readily.

While the invention has been shown and described in terms of a preferredembodiment many changes and modifications will be obvious to thoseskilled in the art without departing from the true spirit and scope ofthe invention as defined in the appended claims.

What is claimed is 1. Apparatus for dressing side surfaces of a grindingwheel comprising a base, means to swing said base in a plane parallel tosaid side surfaces, a pair of supporting members mounted on said base onthe opposite sides of said grinding wheel, a first shaft rotatablymounted in each of said supporting members, a rotary dressing toolmounted on each first shaft, a second shaft drivingly connected todriving means, and a drive connection between said second shaft and eachfirst shaft.

2. The dressing apparatus according to claim 1, wherein there arefurther provided means for moving each supporting member and hence therotary dressing too] associated therewith toward and away from each sidesurface of said grinding wheel, and means for preventing said driveconnection from being released upon movement of each supporting membertoward and away from each side surface of said grinding wheel.

3. The dressing apparatus according to claim 2, wherein said secondshaft is disposed in parallel with the axis of said grinding wheel andsaid drive connection comprises a bevel gear secured to one end of eachfirst shaft, and a bevel gear keyed to said second shaft and meshingwith said first mentioned bevel gear.

4. The dressing apparatus according to claim 2 wherein said basecomprises a sleeve rotatably mounted on a third shaft, and said base isoscillated about said third shaft together with said supporting membersand said rotary dressing tools by means of a double acting pistoncylinder assembly.

5. The dressing apparatus according to claim 2 wherein said means formoving each supporting member comprises an adjusting bolt threaded intoeach supporting member and sup ported by said base.

6. The dressing apparatus according to claim 2 wherein said movement ofsaid supporting member towards and away from the side surfaces of saidgrinding wheel is guided by guide means located on said base beneathsaid supporting members.

7. The dressing apparatus according to claim 4 wherein said sleeve ofsaid base is operated by said double acting pistoncylinder assemblythrough a worm wheel rotated by said piston-cylinder assembly and meansis provided to lock and unlock the rotation of said worm wheel.

8. The dressing apparatus according to claim 7 wherein means responsiveto a predetermined angle of rotation of said worm wheel are provided forperiodically reversing the operation of said double actingpiston-cylinder assembly.

1. Apparatus for dressing side surfaces of a grinding wheel comprising abase, means to swing said base in a plane parallel to said sidesurfaces, a pair of supporting members mounted on said base on theopposite sides of said grinding wheel, a first shaft rotatably mountedin each of said supporting members, a rotary dressing tool mounted oneach first shaft, a second shaft drivingly connected to driving means,and a drive connection between said second shaft and each first shaft.2. The dressing apparatus according to claim 1, wherein there arefurther provided means for moving each supporting member and hence therotary dressing tool associated therewith toward and away from each sidesurface of said grinding wheel, and means for preventing said driveconnection from being released upon movemEnt of each supporting membertoward and away from each side surface of said grinding wheel.
 3. Thedressing apparatus according to claim 2, wherein said second shaft isdisposed in parallel with the axis of said grinding wheel and said driveconnection comprises a bevel gear secured to one end of each firstshaft, and a bevel gear keyed to said second shaft and meshing with saidfirst mentioned bevel gear.
 4. The dressing apparatus according to claim2 wherein said base comprises a sleeve rotatably mounted on a thirdshaft, and said base is oscillated about said third shaft together withsaid supporting members and said rotary dressing tools by means of adouble acting piston cylinder assembly.
 5. The dressing apparatusaccording to claim 2 wherein said means for moving each supportingmember comprises an adjusting bolt threaded into each supporting memberand supported by said base.
 6. The dressing apparatus according to claim2 wherein said movement of said supporting member towards and away fromthe side surfaces of said grinding wheel is guided by guide meanslocated on said base beneath said supporting members.
 7. The dressingapparatus according to claim 4 wherein said sleeve of said base isoperated by said double acting piston-cylinder assembly through a wormwheel rotated by said piston-cylinder assembly and means is provided tolock and unlock the rotation of said worm wheel.
 8. The dressingapparatus according to claim 7 wherein means responsive to apredetermined angle of rotation of said worm wheel are provided forperiodically reversing the operation of said double actingpiston-cylinder assembly.